People

In addressing the concern of whether the number of people would increase at a rate faster than the food supply, we turn to the pivotal insights of Thomas Malthus, a classical economist and scholar renowned for his work in demographic trends. Malthus postulated his theory in the late 18th century, which has since been influential in the field of Geography and beyond.

Malthusian Theory: According to Malthus, population increases in a geometric ratio (exponentially), whereas food supply can only increase in an arithmetic ratio (linearly). He argued that if unchecked, population growth would outpace agricultural production, leading to widespread scarcity and famine.

This theory is captured in his seminal work, "An Essay on the Principle of Population," first published in 1798. In it, Malthus suggested that while technological advancements could temporarily increase food production, the inherent growth tendencies of the population would still eventually lead to resource shortages.

In conclusion, the correct answer is therefore identified as: Malthus, whose observations have had a lasting impact on demographic studies and the examination of resource management challenges in the face of population growth.

To determine which continent has the highest population density, we need to consider two factors: the total population and the land area of each continent. Population density is calculated using the following formula:

Population Density = Total Population / Land Area

Let's examine each option:

• Africa: Known for its vast lands with deserts like the Sahara, Africa's population density is moderate.
• Asia: Contains countries with some of the largest populations, such as China and India, over a diverse geography, leading to a high population density.
• Europe: A smaller continent with a relatively high population density due to numerous small countries.
• North America: Large countries like the USA and Canada with vast uninhabited areas, leading to a lower population density.

Considering the above evaluation, Asia has the highest density of population owing to the large number of people living in relatively smaller land areas compared to the vast and less populated regions of other continents.

Thus, the continent with the highest population density is Asia.

The main cause of an ageing population is increased life expectancy. As advancements in healthcare, nutrition, and living conditions improve, people tend to live longer. This results in a higher proportion of older individuals within the population. Consequently, this demographic shift leads to an overall older average age of the population.

While increased birth rate could potentially balance an ageing population by introducing more young individuals into the demographic pool, it is not the primary factor causing population ageing. Similarly, a sedentary lifestyle may impact individual health but does not directly influence the population's age structure. Finally, migration can influence population dynamics, but its effect on ageing depends on the age profiles of immigrants and emigrants.

The question requires matching stages of demographic transition with corresponding countries or tribes. Let's examine these stages and the respective matches:

Stages of Demographic Transition

(A) High Fluctuating Stage
This stage is characterized by high birth and death rates, leading to a stable and low population growth. This is typical of pre-industrial societies, often seen in indigenous and remote rainforest tribes. Thus, the match is (A)-(I) Rainforest tribes.
(B) Early Expanding Stage
This stage experiences high birth rates and declining death rates, resulting in rapid population growth. Many developing countries, such as Angola, are in this stage. Hence, (B)-(II) Angola is correct.
(C) Low Fluctuating Stage
This involves low birth and death rates with slow population growth. It's typical of economically developed countries like Japan, indicating stable and low population growth. Therefore, the correct match is (C)-(IV) Japan.
(D) Late Expanding Stage
This stage represents decreasing birth and death rates with moderate growth. Countries like India, which are advancing economically and industrially, fit this. Thus, the appropriate match is (D)-(III) India.

By analyzing these stages, we confirm the correct answer: (A)-(I), (B)-(II), (C)-(IV), (D)-(III).